Q22.2P - Chemistry: Molecular Nature Of Matter And Change

Question

Metallic elements can be recovered from ores that are oxides, carbonates, halides, or sulphides. Give an example of each type.

Step-by-Step Solution

Answer

• Oxides- hematite, magnetite, corundum, limonite 
• Carbonates- calcite, siderite, magnesite, dolomite
• Halides- cryolite, fluorite, halite
• Sulphides- pyrite, chalcopyrite, sphalerite, covellite

Step 1: Ore

Ore is the compound of a metal from which the metal can be extracted with low expenditure.

Step 2: Explanation

Oxides

The oxide anion, ${\mathrm{O}}^{2-}$is found in oxide ores.

For instance:

hematite-${\mathrm{Fe}}_2{\mathrm{O}}_3$

magnetite-${\mathrm{Fe}}_3{\mathrm{O}}_4$

corundum-${\mathrm{Al}}_2{\mathrm{O}}_3$

limonite-$2{\mathrm{Fe}}_2{\mathrm{O}}_3.3{\mathrm{H}}_2\mathrm{O}$

Carbonates

Carbonate ore contains a carbonate anion, ${\mathrm{CO}}_3^{2-}$

For instance:

Calcite-${\mathrm{CaCO}}_3$

Siderite-${\mathrm{FeCO}}_3$

Magnesite-${\mathrm{MgCO}}_3$

Dolomite-$(\mathrm{Ca},\mathrm{Mg})\mathrm{C}{\mathrm{O}}_3$

Halides

Halides ore contains anions of halogen atoms, such as fluorides $\left({\mathrm{F}}^{-}\right)$, chlorides$\left({\mathrm{Cl}}^{-}\right)$, bromides $\left({\mathrm{Br}}^{-}\right)$ or $\left({\mathrm{I}}^{-}\right)$.

For instance:

Cryolite-${\mathrm{Na}}_3{\mathrm{ALF}}_6$

Fluorite-${\mathrm{CaF}}_6$

Halite-$\mathrm{NaCl}$

Sulfides

The sulphides anion, ${\mathrm{S}}^{2-}$, is found in sulphide ores.

For instance:

Pyrite- $\mathrm{FeS}$

Chalcopyrite- ${\mathrm{CuFeS}}_2$

Sphalerite-$\mathrm{ZnS}$

Covellite- $\mathrm{CuS}$

${\mathrm{CaF}}_6$